Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_TIME64_H
3#define _LINUX_TIME64_H
4
5#include <linux/math64.h>
6
7typedef __s64 time64_t;
8typedef __u64 timeu64_t;
9
10#include <uapi/linux/time.h>
11
12struct timespec64 {
13 time64_t tv_sec; /* seconds */
14 long tv_nsec; /* nanoseconds */
15};
16
17struct itimerspec64 {
18 struct timespec64 it_interval;
19 struct timespec64 it_value;
20};
21
22/* Parameters used to convert the timespec values: */
23#define MSEC_PER_SEC 1000L
24#define USEC_PER_MSEC 1000L
25#define NSEC_PER_USEC 1000L
26#define NSEC_PER_MSEC 1000000L
27#define USEC_PER_SEC 1000000L
28#define NSEC_PER_SEC 1000000000L
29#define FSEC_PER_SEC 1000000000000000LL
30
31/* Located here for timespec[64]_valid_strict */
32#define TIME64_MAX ((s64)~((u64)1 << 63))
33#define KTIME_MAX ((s64)~((u64)1 << 63))
34#define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
35
36static inline int timespec64_equal(const struct timespec64 *a,
37 const struct timespec64 *b)
38{
39 return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
40}
41
42/*
43 * lhs < rhs: return <0
44 * lhs == rhs: return 0
45 * lhs > rhs: return >0
46 */
47static inline int timespec64_compare(const struct timespec64 *lhs, const struct timespec64 *rhs)
48{
49 if (lhs->tv_sec < rhs->tv_sec)
50 return -1;
51 if (lhs->tv_sec > rhs->tv_sec)
52 return 1;
53 return lhs->tv_nsec - rhs->tv_nsec;
54}
55
56extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec);
57
58static inline struct timespec64 timespec64_add(struct timespec64 lhs,
59 struct timespec64 rhs)
60{
61 struct timespec64 ts_delta;
62 set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec,
63 lhs.tv_nsec + rhs.tv_nsec);
64 return ts_delta;
65}
66
67/*
68 * sub = lhs - rhs, in normalized form
69 */
70static inline struct timespec64 timespec64_sub(struct timespec64 lhs,
71 struct timespec64 rhs)
72{
73 struct timespec64 ts_delta;
74 set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec,
75 lhs.tv_nsec - rhs.tv_nsec);
76 return ts_delta;
77}
78
79/*
80 * Returns true if the timespec64 is norm, false if denorm:
81 */
82static inline bool timespec64_valid(const struct timespec64 *ts)
83{
84 /* Dates before 1970 are bogus */
85 if (ts->tv_sec < 0)
86 return false;
87 /* Can't have more nanoseconds then a second */
88 if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
89 return false;
90 return true;
91}
92
93static inline bool timespec64_valid_strict(const struct timespec64 *ts)
94{
95 if (!timespec64_valid(ts))
96 return false;
97 /* Disallow values that could overflow ktime_t */
98 if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
99 return false;
100 return true;
101}
102
103/**
104 * timespec64_to_ns - Convert timespec64 to nanoseconds
105 * @ts: pointer to the timespec64 variable to be converted
106 *
107 * Returns the scalar nanosecond representation of the timespec64
108 * parameter.
109 */
110static inline s64 timespec64_to_ns(const struct timespec64 *ts)
111{
112 return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
113}
114
115/**
116 * ns_to_timespec64 - Convert nanoseconds to timespec64
117 * @nsec: the nanoseconds value to be converted
118 *
119 * Returns the timespec64 representation of the nsec parameter.
120 */
121extern struct timespec64 ns_to_timespec64(const s64 nsec);
122
123/**
124 * timespec64_add_ns - Adds nanoseconds to a timespec64
125 * @a: pointer to timespec64 to be incremented
126 * @ns: unsigned nanoseconds value to be added
127 *
128 * This must always be inlined because its used from the x86-64 vdso,
129 * which cannot call other kernel functions.
130 */
131static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns)
132{
133 a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
134 a->tv_nsec = ns;
135}
136
137/*
138 * timespec64_add_safe assumes both values are positive and checks for
139 * overflow. It will return TIME64_MAX in case of overflow.
140 */
141extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs,
142 const struct timespec64 rhs);
143
144#endif /* _LINUX_TIME64_H */